There has been heretofore known a so-called exhaust gas temperature sensor using a thermistor element as a thermal sensing element for detecting the temperature of exhaust gas flowing in an exhaust gas flow path such as the inside of a catalytic converter of an exhaust scrubber of a car or the inside of an exhaust pipe. As this type temperature sensor, there is known a temperature sensor having a structure in which a thermistor element is disposed in the front end side inside of a metal tube shaped like a bottomed pipe while a sheath member having a sheath pipe in which metal cores connected to electrode wires of the thermistor element are held while electrically insulated is inserted into the metal tube (e.g. see Patent Documents 1 and 2). In such a temperature sensor, heat of the exhaust gas is received by the metal tube and then transmitted from the metal tube to the thermistor element to thereby detect the temperature.
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-162051 (FIG. 1)
[Patent Document 2]
Japanese Patent Laid-Open No. 2002-350241 (FIG. 2)